3, 5-dimethyl-4-halo-pyrazoles



United States Patent 3,328,420 3,S-DIMETHYL- t-HALO-PYRAZOLES Tornoyoshi Toyosato, Kyoto, Michihiko Ochiai, Suita, Hircshi Hagimoto and Hiroshi Tamura, Kyoto, and Toshiya Kamikado, Suita, Japan, assiguors to Takeda Chemical Industries, Ltd., Osaka, Japan No Drawing. (lriginal application Aug. 9, 1963, Ser. No. 301,201. Divided and this application Apr. 29, 1966, Ser. No. 560,919

Claims priority, application Japan, Aug. 10, 1962, 37/3 3,645 18 Claims. (Cl. 260-310) This application is a division of application S.N. 301,- 201, filed August 9, 1963.

The present invention relates to novel pyrazole derivatives and to their use for agricultural purposes. More particularly, the said pyrazole derivatives are those of the formula wherein R stands for H, lower alkyl, lower aralkyl or aryl, R stands for H, halogen, nitro, nitroso, cyano or lower alkoxycarbonyl, R stands for H, OH, NI-I lower alkyl, lower aralkyl, aryl or lower alkoxy, and R and R may form abenzene ring or a tetrahydrobenzene ring together with the carbon atoms in 4- and 5-positions of pyrazole ring, X stands for halogen, H, N0 lower alkyl, acyl, hydroxyalkyl, (lower)alkoxy(lower)alkyl or lower alkoxy. A stands for lower alkylene, and n stands for an integer from 1 to 5, inclusive.

The pyrazole derivatives of the above-mentioned formula (I) have the effect to regulate growth of plants and, therefore, by a suitable choice of concentration of the pyrazole derivatives applied to plants and of the application method, the compounds regulate various growth phenomena of various plants, that is, leaf-expansion, shootelongation, root-initiation, fruit-development, fruit-ripening, flower-production and dormancy or, in the case of certain weeds, have a withering action.

There have been reported many kinds of plant growth regulators, but only a few of them are actually utilized for agricultural purposes, because most of them can not be used without risk of harm to desired cultural plants, or the agents are effective only to the non-intact plant, for example, to stem section, leaf disk or callus tissue, or a large amount of the agents is required, or the agents can not be applied to plants before rain or in rain.

Although many attempts have been made to overcome the aforesaid shortcomings and other disadvantages, none, as far as the present inventors are aware, has been entirely successful when applied to practical use.

The present invention provides a series of new pyrazole derivatives of the above-mentioned formula (I), having a remarkable plant growth regulating activity upon application of a small quantity of compound to plants, with no discernible change in activity even in the case of rain just after an application to plants.

' It is an object of the present invention to provide plant growth regulators which are free from the above-mentioned shortcomings or disadvantages. Another object is to provide new pyrazole derivatives.

The present invention also contemplates providing methods for preparation of the said pyrazole derivatives. Among the further objects of the present invention is the provision of plant growth regulators which contain the pyrazole derivatives (I), and their use in regulating plant growth.

3,328,420- Patented June 27, 1967 0=CA-O (I) 1 N Q g if (in NH? I X.. i R2C=GR1 (JO-A-O- (I) In the above-mentioned formulae, Y stands for .a halogen, advantageously Cl, R stands for H or lower alkyl, B stands for an acyl, a cyano, or an alkoxycarbonyl group,

and R R R X, n and A have the same significance as those in the formula (1), respectively.

The alkyl group represented by R R R or X in the foregoing formulae, is lower alkyl and may, for example, be methyl, ethyl, propyl, isopropyl, butyl or the like. As the halogen represented by R X or Y there may be chlorine or bromine. The alkyl group as the constituent of the alkoxycarbonyl group represented by R or B, the alkyl group as the constituent of the alkoxy group represented by R or X, and the alkyl group as the constituent of hydroxyalkyl or alkoxyalkyl represented by X in the formulae are likewise lower 'alkyl (cf. first sentence of the present paragraph).

When the compounds have two or more alkyl groups respectively represented by R R or R they may be the same as or different from each other. In case the number n is greater than 1, each X may be the same as or different from every other X.

Among the acyl groups represented by X or B in the above formulae, there may, for example, be included the formyl, acetyl and benzoyl groups, and among the aralkyl groups represented by R or R there may, for example, be included benzyl and phenethyl groups.

l-methylethylene, Z-methylethylene, l-methylpropylene,

or 2-ethylethylene. Furthermore, R and R may form a' benzene ring or a tetrahydrobenzene ring together with the carbon atoms in 4- and 5-positions of the pyrazole ring.

As previously described, the pyrazole derivatives of the present invention may be provided by the reactions as shown in the above-mentioned reaction formulae (i) or The reaction (i) may be carried out in the presence or absence of a suitable solvent. As solvent, there may be used such organic bases as pyridine, triethylamine, dimeth- ,ylaniline or the usual organic solvents such as acetone, methylethylketone, dimethylformamide, etc. The reaction is generally effected at room temperature (15 to 30 C.), and it may be controlled by heating or cooling, if necessary.

, The reaction (ii) may be carried out in a suitable solvent. The solvent may, for example, be water, methanol, ethanol, acetic acid, benzene, etc., or a mixture consisting of two or more of these solvents. The reaction may be promoted by the addition of a small amount of acid .to the reaction system. The reaction may be effected at The aryl group represented by R or R may, for exroom temperature and may also be controlled by heating or cooling, if necessary.

The following list sets forth a wide variety of pyrazole derivatives prepared by the method of the present invention, which are useful as plant growth regulators according to the present invention:

(1) 1 (2,3,6 trichlorophenoxyacetyl) 3,5-dimethyl-4-chloropyrazole;

(2) 1 (2,4 dinitrophenoxyacetyl) 3,5-dimethyl-4- bromopyrazole;

(3) 1 (2,4 dinitrophenoxyacetyl) 3,5 dirnethyl-4- chloropyrazole;

(4) 1 (2 ethylphenoxyacetyl) 3,S-di(p-nitrophenyl) -4-bromopyrazole;

(5) 1 (2 formyl 4 chlorophenoxyacetyl)-3,5- dimethyl-4-chl0ropyrazole;

(6) 1 (2 u formyl 4 chlorophenoxyacetyl)-3,5-dimethyl-4-bromopyrazole;

(7) 1 (2,3,6 trichlorophenoxyacetyl) 3,5-dimethyl-4-bromopyrazole;

(8) 1 (2,3,6 trichlorophenoxyacetyl) 3,5-diethyl- 4-chloropyrazole;

(9) 1 (3 methoxyphenoxyacetyl) 3,5-dimethyl-4- chloropyrazole;

(10) 1 (2 chlorophenoxyacetyl) 3,5-dimethyl-4- chloropyrazole',

(ll) 1-(2 hydroxymethyl 4 chlorophenoxyacetyl)- 3,5-dimethyl-4-chloropyrazole;

(12) 1-(2,4-dinitrophenoxyacetyl) 3,5 diethyl-4-bromopyrazole.

In practice, and to realize the desired activity, the plant growth regulators of the present invention are advantageously applied to plants in the form of the compositions such as dust, emulsion, suspension or solution. In other words, the plant growth regulator compositions of the present invention comprise essentially at least one active compound (pyrazole derivative) represented by the abovementioned formula (I) together with a suitable carrier (e.g. extender and/or conditioning agent) of the type commonlyemployed for the carriers of a known growth control agent. It is not intended, in this respect, that the present invention be limited to any specific proportions of active ingredient(s) (I) and adjuvant.

The compositions may be readily prepared ab initio or may e.g. be in the form of concentrates comprising active ingredient (I) with only a minor amount of an adjuvant, e.g. a surface active agent. Such a concentrate is economical as regards transportation, storage and the like, and may easily be admixedprior to usewit-h additional adjuvant to give the desired concentration of the active ingredient when it is applied. The adjuvant may be selected depending on plants to be treated, properties of active ingredient and other adjuvant to be used together, and conditions of use.

Thus, if both the active ingredient and adjuvant(s) are water-soluble, the composition may be applied in the form of an aqueous spray. If, for example, a water, insoluble adjuvant is employed-e.g. if the composition comprises ,a water-insoluble adjuvant the composition may be applied as an aqueous dispersion. It is also possible e.g. merely to mix the active agent, in powder form, with a powdery adjuvant and to use the mixture (dust). Or, the powder mixture may be suspended in water or in an oil, such as gasoline, kerosene, etc., which, upon mixing with water, forms e.g. an oil-in-water emulsion containing the active ingredient. When the compositions are used in dust form, the adjuvant (or diluent) may e.g. be talc, clay, diatomaceous earth, lime, calcium sulfate, kaolin and the like.

When the compositions are used in the form of liquid, the adjuvant (diluent) is e.g. water, an aqueous solvent, a volatile or non-volatile organic solvent, e.g. an alcohol such as methanol, ethanol, etc., a ketone such as acetone, methylethylketone, etc., an ether such as dioxane, tetrahydrofuran, etc., an aromatic hydrocarbon such as benzene, toluene, xylene, etc., a halogenated hydrocarbon such as chloroform, carbon tetrachloride, etc., an ester such as ethyl acetate and oil, etc. the composition-as aforeindicated-taking the form of a solution, emulsion or suspension depending on the nature of the materials employed.

The new plant growth regulating compositions may further contain wetting agents, dispersing agent and emulsifiers such as suitable surface active agents, e.g. polyoxethyleneglycolethers, polyoxyethyleneglycolesters, polyoxyethylene derivatives of sorbitan monolaurate (monooleate, monostearate), polyoxyethylenealkylarylether, alkyl sulfonate, alkylaryl sulfonate, alkyl sulfosuccinate, etc. They may also contain adherent or sticking agents, and also other agricultural chemicals, e.g. pesticides, fungicides, manure or fertilizer growth controlling agents, plants hormone, etc., all these materials being considered adjuvants.

It is within the scope of the present invention to employ other adjuvants than those hereinbefore mentionede.g. solid or liquid diluents, emulsifiers, dispersants, surface active agents or otherwiscthose already mentioned being merely illustrative.

The essence of the present invention does not reside in any specific adjuvant but in a composition consisting essentially of at least one compound of the formula (I) and an appropriate inert agricultural adjuvant which does not prejudice the activity of the composition.

Generally speaking, an effective amount for plant growth regulation is satisfied with the following quantitative relationships.

A dust or oil composition for direct application to plants may contain from 0.00001 percent to 10 percent or more of the active ingredient(s) by weight. When the composition is prepared for actual use in the form of sprays or more dilute dusts, the content of the active ingredient(s) may vary from about 0.01 percent to as high as 0.1 percent by weight, the balance of the composition being one of the diluents and/or surface active agents (adjuvants) previously mentioned.

Content of the active ingredient in an aqueous dispersion may similarly vary from a very low percentage, e.g. 1 percent by weight, where the dispersion is applied directly to plants, to a relatively high percentage, e.g. percent by weight, where the dispersion is employed as a concentrate, thebalance in each case being constituted by an adjuvant or adjuvants.

The plant growth regulators of the present invention promote leaf-expansion, shoot-elongation, root-initiation, fruit-set, fruit-development, fruit-ripening, flower-production or break dormancy of plant (bud or seed), or induce parthenocarpy, or inhibit absciss-layer formation at a considerable low concentration and inhibit growth or kill weeds at a considerable high concentration.

Among these uses of the present plant growth regulators effects on the regulation of fruit-development, i.e. effects on inducing parthenocarpy, inhibition of abscisslayer formation, fruit-drop prevention, stimulation of fruit-development, stimulation of fruit-ripening, and effect on suppressing or withering weeds are very prominent.

Heretofore, p-chlorophenoxy acetic acid, fl-naphthoxy acetic acid, 2,4-dichlorophenoxy acetic acid, 2,4,5-trichlorophenoxypropionic acid, a-naphthalenacetic acid or a mixture of two or three of these have been put to use for fruit-drop prevention or fruit-set stimulation, expecting their hormonal effect. These known compounds, however, are not free from the shortcomings that a large amount of the agents must be applied, or that the agents may do auxonic (hormonal) injury to plants to which they are applied.

The plant growth regulators of the present invention, on the other hand, display a superior hormonal effect on plants in spite of the application of a lesser amount in comparison with the above-mentioned compounds or their mixtures.

In application of the plant growth regulator of the present invention to plants for the purpose of growth promotion of the plants, it can be applied or sprayed onto seeds, roots, sprouts, stems, leaves, flowers, flower clusters, fruits, etc., in a suitable concentration for the purposes.

In application of the plant growth regulator of the present invention to plants for the purpose of growth inhibition of the plants or weeds, it can be applied to soil in pro-emergence of the plants or in post-emergence in a suitable concentration for the purpose.

In the treatment of paddy field weeds, the plant growth regulator may directly be applied to the plants or in paddy field where the plants grow. The plant growth regulator of the present invention can cause contact and auxonic (hormonal) injury, growth inhibition or withering of weeds by direct or indirect contact therewith, and moreover, the plant growth regulator displays inter-genus-selectivity among gramineous plants.

Examples of regulative effect upon plant growth by application of the pyrazole derivatives (I) are set forth as follows:

EXAMPLE A Growth promotion test Growth-promoting and inhibiting action of the present compounds were tested by the Avena straight growth method. Ten pieces of 5 millimeter length of subapical section of Avena coleoptiles were soaked in the solution for 24 hours at 25 C. in the dark and their lengths were measured under the travelling microscope.

In the table, the compounds are represented by the corresponding numbers shown below:

1-(2,4-clichlorophenoxyacetyl) 3,5 dirnethylpyraz- 1 p.p.m. means concentrations in parts per million.

EXAMPLE B Fruit-set and fruit-development test (1) Conditions Tested plant: Tomato (Lycopersicon esculentum: Mill) Test scale: 20 pots (1/2000 are Wagners pot) per one plat, per one plant per one pot, 2 repetitions The term plot used in following examples means a definite treated area of experiment in which the preparation of this invention is applied, in other words, for example, 20 pots 1 plot used in EX- arnple B has such a meaning that the preparation of this invention having a certain concentration is applied to 20 pots, respectively. This is applicable to the same term used in all other examples.

Method: Respective aqueous solutions each containing one of the following six compounds in various concentration are applied to the flowers with a brush, and days required for ripening and the features of fruit-set and fruit-development were observed.

ole I (2) Result 1-(4-chlorophenoxyacetyl)-3,5'-dimethylpyrazole H r In the following two tables, the compounds are repre- 1 (2,3,6-trichlorophenoxyacetyl) 3,5 dimethyl-4- 40 sented by the corresponding numbers shown below:

chloropyrazole 111 1(2,4 dichlorophenoxyacetyl) 3 y p 1 0122A dichlorophenoxyacetyl) 3,5 dimethylpyraz I l razole IV 1 2 trichlorophenoxyacetyl) 3 5 dimethyb 1-(4-chlorophenoxyacetyl)-3,5-d1methylpyrazole II pyrzole V 1 (2,4,5 trichlorophenoxyacetyl)-3,5-dimethyl-4- 1'[IX (2,4-dichlorophenoxy)propionyl] 3 ,5 di- 45 chloropyrazole III lnethylpyrazole VI 1 (2 frmyl-4-chlorophenoxyacetyl)-3,5-dirnet-hyll(2,4-dichlorophenoxyacetyl)indazole VII P 3116 1V l-(2-hydroxymethyl 4 chlorophenoXy-acetyl)-3,5- 1 Y p y y Y dimethylpyrazole V111 50 4-chloropyrazole V 1-(2,4,S-trichlorophenoxyacetyl) 4,5,6,7 hexahy- 1 y p y y Y droindazole IX phenylpyrazole VI TABLE I Fruit-development (millimeter) Average Percentage weight of Days required Compounds Cone, of fruit-set Mean value of Mean value of treated fruit for ripening ppm. (percent) diameter of diameter of in the harvest (days) fruits 14 days fruit in the time after the apharvest time (grams) plication Control (water)... 0 48. 3 27 x 27 54 x 43 128. 2 40. 3 1 77. 2 31 x 31 58 x 48 137. 4 35. 5 I 93.1 39 x 36 67 x 51 145. 5 32. 3 87.7 x 35 65 x 51 140. 9 33.1 40 35. 4 37 x 31 64 x 51 140. 2 33. 4 1 53. 7 27 x 27 54 x 43 127. 7 39. 2 H 10 57. 6 30 x 23 54 x 45 129.1 37. 1 20 59. 3 32 x 31 54 x 45 12s. 9 37.1 40 60.1 33 x 30 x 49 132.5 35. 9 1 51. 6 28 x 27 54 x 45 128.3 39. 2 In 10 57. 4 29 x 27 55 x 47 123. 0 3s. 7 20 53. 7 30 x 23 56 x 47 129. 2 37.1 40 63.5 32 x 31 53 x 48 132. 6 35. s

1 Cone. means concentration.

TABLE H EXAMPLE D Growth inhibition test of young stage plants Fruit-develop- Days ment (average required (1) Conditions Compounds Conc., Percentage weight of treated for {LP-1112 offruiteset fruitin t pg 5 Tested plants: RIC/3 (Oryza satzvd L.), Cucumber zg g g ay) (Cu'cumis sativus L.) and Cocks foot (Panicum crusgalli L.) Controuwatenfl 412 126 0 4M Test scale: 10 seeds per one plot. 3 repetitions Iv 1 g Method: Germinating seeds of equal state of germi- 8 31 31 1 10 nation are placed in a petri-dish (diameter: 9 cm.) 128 29.3 g g-2 on which filter paper. is spread and respective 5 cubic v 2O 3 1 6 3 centimeters of the suspensions of each containing one s ggof the following compounds are poured. Then they 10 13011 1 p are incubated at 25 C. in the dark VI 20 55. 4 132. 5 3s. 0

i 40 60i3 135.3 36.5 (2) Result Five days after treatment, root length and stem length 1 oonc meansconcentmtion are respectively measured to calculate inhibitionper- 2 p.p.m. means parts per million. centages.

EXAMPLE C (1) Conditions Fruit-set promotion test Tested plants: Eggplant (Solanus melongena) Test scale: one plant per one pot; pots (1/2000 are Wagners pot) per 1 plot, 2 repetitions Method: The solutions ofthe following four com- Inhibition percentage treated root length (treated'stem length) 1 100 non-treated root length X (non-treated stem length) Plant Rice (Oryza Cucumber Cocks ioot sativa L.) (Cncmnz's (Panicum sativus L.) crusgalli L.) p.p.m.

Inhibition Percentage (Percent) root stem root stem root stem length length length length length length 1 95 5 90 0 90 62 1-(4-chloro-phenoxyacctyl)- ll 10 95 0 100 20 93 91 3,5-chmethyl-pyrazole. 100 93 0 100 38 93 93 1(2,4-dichlorophenoxy- 1 100 0 100 57. 9 84. 5 49. 6 acetyl)-3,5-dimethyl-pyraz- 10 100 53. 6 97. O 0 84. 7 61. 4 ole. 100 100 100 100 0 88. 5 66. 3

1 ppm. means parts per million.

EXAMPLE E pounds are applied to flowers and peduncles with a brush. (2) Result In the following table, the compounds are represented by the corresponding numbers shown below:

1 (2,4 dichlorophenoxyacetyl)-3,5-dimethylpyraz- 1 ppm. means concentrations in parts per million.

Growth inhibition and withering test by spray method at post-emergence (1) Conditions Test plants: Rice, Soybean (Glycine max Merrill), Buckwheat (Fagopyrum esculentum Moench) and 2) Observation Fourteen days after. treatment, results are examined to calculate inhibition percentages and withering percentages.

Inhibition percentage Fresh weight at treated plot Fresh weight at non-treated plot Withering percentage )XlOO Number of completely withered plant Number of used test plant X 100 (70) 9 I (3) Result 1 (4 chloro-2-methylphenoxyacetyl) 3,5-dimeth- In the following table, the compounds are repreylpyrazole sented by the corresponding numbers shown below. 1 tl'lchlofophenoxyacetyl)3541111631311- 1e 1 (2,4-dichlorophenoxyacetyl)-3,5-d1methylpyrazole I pyrazo 1 (2 formyl-4-chlorophenoxyacetyl)-3,5-di 1 1 (4-chlorophenoxyacetyl)-3,5-d1methyl-4-chlor0- 4 chloropyrazole II PY 1 l3 (Z-hydroxymethyl-4-chlorophenoxy)propionyh' 1 dlchlorophenoxyacetyl) Y 3,5-dimethyl-4-nitrosopyrazole III chloropyrazole TABLE Plants Concentra- Compounds on Rice Soy beans Tomato Buck wheat (Percent) Inhibition Withering Inhibition Withering Inhibition Withering Inhibition Withen'ng (Percent) (Percent) (Percent) (Percent) (Percent) (Percent) (Percent) (Percent) Concentrations in the present example are shown (1) Conditions EXAMPLE F by weight-percentage.

1 (2,4,5 trichlorophenoxyaceyl) 3,5 dimethyl- 4 chloropyrazole 1 (2 chlorophenoxyacetyl) 3 chloromethyl-4- nitrosopyrazole 3O 1 (2,4-dichlorophenoxyacetyl) 3,5 dimethyl-4- Tested plants: Rlce, soy bean, buck wheat and tomato nltfopyl'alole Test scale: 1 pet (1/ 5000 are Wagners pot) per 1 plot, 1 (4 chlorophenoxyacetyl) 3,5 dunethylpyrabout 10 plants per pot, 2 repetitions. azole VIII Method: Respective 10 cub1c centimeters of the solu- 1 (2,4-d1chlorophenoxyacety1) 3,5 dimethyltlons of, the following compounds per one plot is ap- 0 pyrazole Plants Concentra- Compounds tion Rice Soy been Tomato Buck wheat (Percent) Inhibition Withering Inhibition Withering Inhibition Withering Inhibition Withering (Percent) (Percent) (Percent) (Percent) (Percent) (Percent) (Percent) (Percent) 0. 5 9. 1 0 100 100 77. 0 58. 0 26.8 0.05 27.3 0 100 100 0 0 0 III 0. 01 27.3 0 74.8 66. 7 11. 0 0 0 0.5 0 I 0 100 100 53.0 25.0 10.8 0.05 18. 2 0 100 100 73. 1 50.0 39. 3 IV 0.1 0 0 100 100 100 100 12. 5

0. 5 27.3 0 100 100 100 100 100 0.05 0 0 21.6 0 0 0 0 VI 0.1 0 0 18. 2 13. 4 0 16. 4 0. 5 0 0 100 100 90.0 20. 5 0. 05 0 0 10. 3 100 100 20. 5 VII 0. 1 0 0 22.8 0 100 100 26.6

0. 5 50 0 100 100 100 100 100 0.1 0 0 100 100 100 100 76. 0 VIII 0. 5 0 0 100 100 100 100 86. 8

Concentrations in the present example are shown by weight-percentage.

plied to soil at pro-emergence. EXAMPLE G (2) Result Test for Fruit-drop Prevention One month after treatment, the result is examined to 70 1) Condition calculate inhibition percentages and withering percentages. Inhibition percentages and withering percentages have the same meaning as those defined in Example E.

In the following table, the compounds are represented by the corresponding numbers shown below.

Test plant: Apple (Malus pumile Mill var dulcissima Koidz) Method: Solutions of various concentrations containing 1 (2,4-dichlorophenoXyacetyl-3,S-dimethylpyr- 75 azole are applied to fruits and fruit-stalks about 1 1 one month before the harvest time, and the difierence in the number of dropped fruits between treated trees and non-treated ones is observed.

For the purpose of giving those skilled in the art a better understanding of. the present invention, the following illustrative examples of presently-preferred embodiments of preparations of pyrazole derivatives and of the compositions containing pyrazole derivatives. In these examples, parts and percentages are by weight.

EXAMPLE 1 An emulsion comprising 0.1 part of 1-(4-chlorophenoxyacetyl) 3,5-dimethylpyrazole, 0.3 part of polyoxyethylenesorbitane monolaurate, 50 parts of acetone and 49.6 parts of benzene, according to the invention, is useful in promoting fruit-set and fruit-ripening.

EXAMPLE 2 A solution comprising 0.2 part of 1-'(2,4-dich1orophenoxyacetyl)-3,5-dimethylpyrazole, 0.8 part of polyoxyethylene-alkylarylether and 99 parts of acetone, according to the invention, is useful in promoting fruit-set'and fruitdevelopment.

EXAMPLE 3 An emulsion comprising 0.5 part of 1-(2,4-dichlorophenoxyacetyl)-3,5-dimethyl-4-chloropyrazole, 1.5 part of polyoxyethylenesorbitane monolaurate and 98 parts of methylnaphthalene, according to the invention, is useful in promoting fruit-set and fruit-development.

EXAMPLE 4 A tablet comprising 0.1 part of 1-(2,4-dich1orophenoxyacetyl)-3,5-dimethylpyrazole in 97 parts of lactose, 10

parts of polyethylene glycol (5% methanol solution), 1.2 part of starch, and 1.2 part of talc, according to the invention, is useful in promoting fruit-set and fruit-develop- I ment.

EXAMPLE 5 A tablet comprising 0.2 part of 1-(2,4,5-trichlorophenoxyacetyl)-3,5-dirnethylpyrazole in 96.9 parts of lactose, parts of polyethylene glycol (5% methanol solution),

1.2 part of starch and 12 part of talc, according to the invention, is useful in promoting fruit ripening.

EXAMPLE 6 A powder comprising 2 parts of 1-(4-chlorophenoxyacetyl)-3,5-dimethylpyrazole and 98 parts of talc, according to the invention, is useful in promoting root-initiation.

EXAMPLE 7 A wetting powder comprising 20" parts of 1-(2,4-dich1orophenoxyacetyl)-3,5-dimethylpyrazole, 4 parts of sodium ligninsulfonate, 4 parts of polyoxyethylenealkylarylether and 72 parts of clay, according to the invention, is useful in withering weeds.

EXAMPLE 8 An emulsion comprising 20 parts of l-(2,4-dinitrophenoxyacetyl)-3,5-dimethyl-4-chloropyrazole, 10 parts of methylnaphthalene, according to the invention, is useful in withering weeds.

EXAMPLE 9 A granule comprising 2 parts of 1-(2,4-dichlorophenoxyacetyl)3,5-dimethylpyrazole and 98 parts of bentonite, according to the invention, is useful in withering weeds.

The following examples set forth presently-preferred exemplary embodiments of the preparation of compounds (I).

EXAMPLE 10 To a mixture of 20 parts of ethanol and .5 parts of water are added 2 parts'of 4-chlorophenoxyacethydrazide, 1 part of acetylacetone and 0.3 part of 10% hydrochloric acid, and the mixture is refluxed for 2 hours. After cooling, the separated crystals are recrystallized from ethanol to give 1-(4-chlorophenoxyacetyl)-3,5-dimethylpyrazole as colorless scales melting at 112-113 C. Yield 2 parts.

Analysis.Calculated: c, 58.98% H,'4.95% N, 10.58%.

Found: C, 59.14%; H, 4.82%; N, 10.32%.

EXAMPLE 11 To 30 parts of ethanol are added 2.3 parts of 2,4-dichlorophenoxyacethydrazide, 1 part of acetylacetone, and

0.3 part of 10% hydrochloric acid, and the mixture is refluxed for 1.5 hours. After cooling, the separated crystals are recrystallized from ethanol to give 1-(2,4-dichlorophenoxyacetyl),-3,5-dimethylpyrazole as colorless needles melting at 132-134 C. Yield 2.5 parts.

Analysis.Calculate-d: C, 52.19%; H, 4.04%; N, 9.36%.

Found: C, 52.40%; H, 4.25%; N, 9.29%..

EXAMPLE 12 To a mixture of 20 parts of ethanol and 10 parts of water are added 2 parts of 2-chlorophenoxyacethydrazide, 1 part of acetylacetone and 0.3 part of 10% hydrochloric acid, and the mixture is allowed to react at,50 C. for 6 hours. After cooling, the separated crystals are recrystallized from ethanol to give 1-(2-chlorophenoxyaoetyl)3,5- dimethylpyrazole as colorless prisms melting at-124-126 C. Yield 1.5 parts.

Analysis.Cal-culated: C, 58.98%; H,'4.95%;N, 10.58%.

Found: C, 59.05%; H, 4.99%; N, 10.48%.

EXAMPLE 13 To a mixture of 30 parts of ethanol and 10 parts of water are added 2.3 parts of 2,4-dich1orophenoxyacethydrazide, 1.6 parts of benz-oylacetone and 0.3 part of 10% hydrochloric acid, and the mixture is allowed to react at 60 C. for 10 hours. After coooling, the separated crystals'are recrystallized from ethanol to give 1-(2-,4-di chlorophenoxyacetyl)-3-methyl-5-phenylpyrazole as colorless needles melting at 118-1 19 C. Yield 1.6 parts.

Analysis.Calculated: C, 59.86%; H, 3.90%; N, 7.75%.

Found: C, 60.01%; H, 3.77%; N, 7.26%.

EXAMPLE 14 To a mixtureof 50 parts of ethanol, 20' parts of water, and 10 parts of 10% hydrochloric acid are added 4.6 parts of 2,4-dichlorophenoxyacethydrazide and 3.4 parts of ethyl ethoxymethylenecyanoacetate, and the mixture is stirred at room temperature (20 to 30 C.) for 5 hours. The separated crystals are recrystallized from ethanol to give 1-(2-4,-dichlorophen-oxyacetyl)-4-ethoxycarbonyl-S-aminopyrazole as colorless crystals melting at 162 C. Yield 2 parts.

Analysis.-Calculated: C, 46.95%; H, 3.65% N, 12.01%.

Found: C, 46.23%; H, 3.67%; N, 11.63%.

13 EXAMPLE 15 To a mixture of 30 parts of ethanol, parts of Water and 0.2 part of hydrochloric acid are added 2.1 parts of 4-chloro-2-methylphenoxyacethydrazide and 1 part of acetylacetone. The mixture is heated at 60 C. for 3 hours. After cooling, the separated crystals are recrystallized from ethanol to give 1-(2-methyl-4-chlorophenoxyacetyl)-3,5-dimethylpyrazole as colorless prisms melting at 137.5-138.5 C. Yield 2 parts.

Analysis.Calculated: C, 60.32%; H, 5.42%; N, 10.05%.

Found: C, 60.33%; H, 5.53%; N, 10.32%.

EXAMPLE 16 To a mixture of 35 parts of ethanol, 5 parts of Water, and 0.3 part of 10% hydrochloric acid are added 2.7 parts of 2,4,5-trichlorophenoxyacethydrazide, 1 part of acetylacetone, and the mixture is refluxed for 1.5 hours. After cooling, the separated crystals are recrystallized from ethanol to give 1-(2,4,S-trichlorophenoxyacetyl)-3,5-dimethylpyrazole as colorless melting at 177-178 C. Yield 1.9 parts.

Analysis.Calculated: C, 46.76%; H, 3.32%; N, 8.39%.

Found: C, 46.74%; H, 3.35%; N, 8.37%.

EXAMPLE 17 EXAMPLE 18 To a mixture of 35 parts of ethanol, 5 parts of water and 0.3 part of 10% hydrochloric acid are added 2 parts of 4-chlorophenoxyacethydrazide and 1.3 part of 3-chloron-pentane-2,4-dione, and the mixture is heated at 60 C. for'1.5 hours. After cooling, the separated crystals are recrystallized from ethanol to give 1-(4-chlorophenoxyacetyl)-3,5-dimethyl-4-chloropyrazole as colorless plates melting at 1'51-153 C. Yield 1.3 parts. Analysis.-Calculated: C, 52.19%; H, 4.04% N, 9.36%.

Found: C, 51.69%; H, 3.85%; N, 8.84%.

EXAMPLE 19 To a mixture of 40 parts of ethanol, 10 parts of water and 0.5 part of 10% hydrochloric acid are added 2.3 parts of 2,4-dichlorophenoxyacethydrazide and 1.3 parts of 3-chloro-n-pentane-2,4-dione, and the mixture is refluxed for 1 hour. After cooling, the separated crystals are recrystallized from ethanol to give 1-(2,4-dichlorophenoxyacetyl)-3,5-dimethyl-4-chloropyrazole as colorless needles melting at 127-128 C. Yield-2 parts.

Analysis-Calculated: C, 46.76%; H, 3.32%; N, 8.39%.

Found: C, 46.88%; H, 3.37%; N, 8.16%.

EXAMPLE 20 To a mixture of 35 parts of ethanol, 15 .parts of water and 0.7 part of 10% hydrochloric acid are added 2.7 parts of 2,4,5-trichlorophenoxyacethydrazide and 1.3 parts of 3-chloro-n-pentane-2,4-dione. The mixture is heated at 60 C. for 2 hours. After cooling, the separated crystals are recrystallized from ethanol to give 1-(2,4,5-trichlorophenoxy-acetyl)-3,5-dimethyl-4-chloropyrazole as colorless scales melting at 136.5-138 C. Yield 2 parts.

Analysis.-Calculated: C, 42.42%; H, 2.74%; N, 7.61%.

Found: C, 42.28%; H, 2.84%; N, 7.64%.

14 EXAMPLE 21' To a mixture of 40 parts of ethanol, 10 parts of Water and 0.5 part of 10% hydrochloric acid are added 2 parts of 2-chlorophenoxyacethydrazide and 1.5 parts of 3-nitrou-pen-tane-2,4,-di0ne, and the mixture is refluxed for 1 hour. After cooling, the separated crystals are recrystallized from ethanol to give l-(2-chlorophenoxyacetyl)-3,5- dimethyl-4-nitropyrazole as colorless prisms melting at 192193 C. Yield 1.3 parts.

Analysis.-Calculated: C, 50.41%; H, 3.90%, N, 13.57%.

Found: C, 50.40%; H, 4.22%; N, 13.55%.

EXAMPLE 22 To a mixture of 40 parts of ethanol, 10 parts of Water and 0.5 part of 10% hydrochloric acid are added 2 par-ts of 4-chlorophenoxyacethydrazide and 1.5 parts of 3-nitron-pentane-2,4-dione, and the mixture is refluxed for 1 hour. After cooling, the separated crystals are recrystallized from ethanol .to give 1-(4-chlorophenoxyacetyl)-3,5- dimethyl-4-nitropyrazole as colorless needles melting at 184-186 C. Yield 1.4 parts.

Analysis-Calculated: C, 50.41%; H, 3.90%; N, 13.59%.

Found: C, 50.65%; H, 4.03%; N, 14.03%.

EXAMPLE 23 To a mixture of 35 parts of ethanol, 5 parts of water and 0.5 part of 10% hydrochloric acid are added 2.3 parts of 2,4-dich1orophenoxyacethydr-azide and 1.5 parts of 3- nitro-n-pentane-2,4 iione, and the mixture is refluxed for 2 hours. After cooling, the separated crystals are recrystallized from ethanol to give l-(2,4-dichlorophenoxyacetyl)- 3,5-dimethyl-4-nitropyrazole as colorless prisms melting at 161l62 C. Yield 1.7 parts.

Analysis.Calculated: C, 45.37%; H, 3.22%; N, 12.21%.

Found: C, 45.54%; H, 3.32%; N, 12.26%.

EXAMPLE 24 To a solution of 1.5 parts of 3,5-dimethylpyrazole in 5 parts of pyridine, is dropwise added 2,4-dichlorophenoxyacetylchloride. After the mixture is stirred for 1 HFII, 40 parts of Water are added. The separated crystals are recrystallized from acetone-Water to give 1-(2,4-di-- chlorophenoxyacetyl)-3,5-dimethylpyrazole as colorless needles melting at 132*l34 C. Yield 2.4 parts.

Analysis.-Calculated: C, 52.19%; H, 4.04%; N, 9.3%. Found: C, 52.06%; H, 4.01%; N, 9.63%. l

' iEXAMPLE 2s A mixture of 1.5 parts of 3,5-dimethylpyrazole and 3 parts of 4-chlorophenoxyacetylchloride is heated at C. for 2 hours. After cooling, 40 parts of water is added to the reaction mixture. The separated crystals are re crystallized from acetone-water to give 1-(4-chloro-' phenoxyacetyl)-3,5-dimethylpyrazole as colorless scales;

melting at 112-113" C. Yield 2.8 parts.

Analysis-Calculated: C, 58.98%; H, 4.95%; N, 10.58%.

Found: C, 59.14%; H, 4.82%; N, 10.32%.

EXAMPLE 26 To a solution of 1.6 parts of 3,5-dimethyl-4-chloropyrazole in 5 parts of pyridine, is added dropwise a solution of 3 parts of 2,4,5-trichlorophenoxyacetylchloride in 5 parts of acetone. After one hours stirring, 100 parts of Water are added to the reaction mixture. The separated crystals are recrystallized from acetone to give 1-(2,4,5- trichlorophenoxyacetyl)-3,5 dimethyl-4-chloropyrazole as colorless scales melting at 1365-138 C. Yield 3.2 parts.

Analysis.Calculated: C, 42.42%; H, 2.74%; N, 7.6 1%. Found: C, 42.28%; H, 2.84%; N, 7.64%.

TABLE-Continued R R R A X,. Melting Solvent for Appearance oi point C.) recrystallization crystals CH; C] COH5- CHg- 2-NO'- D0. CH3 Bl CBH5 CHz- 2-NO1- D- 0113- H CzHsO- CH2 2-N0g Colorless crystals. c a- H CH3- CH- 3-N0z- Colorless prisms. CHz- NO: CH3 CHz 3-N0q- Do. CH; Cl CH;- CH; 3-N02- Do. CH3 Br CH3 CHz- 3-N02- Colorless crystals. CHa- H C HO CHg- 3-N0 Colorless prisms. 0113- H CflH5 CH 3-NO;- Do. OH3 Cl C H5- CH2 3-NO, Do. CH; Br CaHv- CH; 3-N0 Colorless crystals. CH3- CH3 CH1 4-NO; Colorless scales. CH3- NO; CH CH 4-NO, Colorless crystals. CH3 Cl CH CH 4-NO, Colorless prisms. CH3-- Br CH3 CH 4-N0 Do. CH3 H CflH5- CH 4-NO Colorless plates. CH3- Cl CaH5 CH 4-N07 Colorless needles. CH3 B1 O5H5- OH7 4-N0g D0. CH:- H CH5 CH 2,3,4,6-tetraCl Colorless crystals. 0113- C1 CH CH 2,3,4,6-tetra-Cl Colorless prisms. CH3 H CeHr- OH2 2,3,4,6-tetra-Cl D0. CH3 CH3- CH2- 2,3,4,5,6-penta-Cl Colorless crystals. CH Cl CH3 CH 2,3,4,5,6-penta-Cl D0. H (CH CH 4Cl Do. H CH: 4-01 Do. H C CH 2,4-di-Cl Colorless needles. H CH= CH-CH CH -CHg- 2,4,5-tri-Cl Colorless crystals. H CH E CH-CH CH- --CH (CH3)- 2,4-di-Cl Colorless needles.

Although the present invention has been described in conjunction with preferred embodiments, it is to be understood that modifications and variations may be resorted to Without departing from the spirit and scope of the invention, as those skilled in the art will readily understand. Such modifications and variations are considered to be within the purview and scope of the invention and dimethyl-4-bromopyrazole.

chloropyrazole.

chloropyrazole.

12. 1- (2,4,5 -trichlorophenoxyacetyl -3,5 dimethy1-4- appended claims. chloropyrazole.

Having thus disclosed the invention, what is claimed is: 13. 1-(2,4,S-trichlorophenoxyacetyl)-3,5-dimethyl-4- 1. 1-(2-chlorophcnoxyacetyl)-3,5-dimethyl-4- bromopyrazole.

chloropyrazole. 3 14. 1-(2-nitrophenoxyacetyl)-3,5-dimethyl-4- 2. 1(3-chlorophenoxyacetyl)-3,5-dimethyl-4- chloropyrazole.

chloropyrazole. 15. 1-(3-nitrophenoxyacetyl)-3,5-dimethyl-4-chloro- 3. 1-(4-chlor0phenoxyacetyl)-3,5-dimethyl-4- pyrazole.

chloropyrazole. 16. 1-(4-nitrophenoxyacetyl)-3,5-dimethyl-4-chloro- 4. 1-(2-methyl-4chlorophenoxyacetyl)-3,5-dirnethylpyrazole. 4-chloropyrazole. 17. 1-(2,3,4,6-tetrachlorophenoxyacetyl)-3,5-di- 5. 1- 2-methyl-4-chlorophenoxy acetyl) -3,5-dimethylmethyl-4-chloropyrazole.

4-bromopyrazole. 18. 1-(2,3,4,5,6pent-achlorophenoxyacetyl)3,5-di- 6. 1-(2,4-dichlorophenoxyacetyl)-3,5-dimethyl-4- methyl-4-chloropyrazole.

chloropyrazole. 7. 1-(2,4-dichlorophenoxyacetyl)-3,5-dimethyl-4- No references citedbromopyrazole.

8. 1-[a( 2,4-dichlorophenoxy)propionyl]-3,5-

dimethyl-4chloropyrazole.

WALTER A. MODANCE, Primary Examiner. NATALIE TROUSOF, Assistant Examiner. 

1. 1-(2-CHLOROPHENOXYACETYL)-3,5-DIMETHYL-4CHLOROPYRAZOLE.
 5. 1-(2-METHYL-4-CHLOROPHENOXYACETYL(-3,5-DEMETHYL4-BROMOPYRAZOLE.
 6. 1-(2,4-DICHLOROPHENOXYACETYL)-3,5-DIMETHYL-4CHLOROPYRAZOLE.
 16. 1-(4-NITROPHENOXYACETYL)-3,5-DIMETHYL-4-CHLOROPYRAZOLE.
 18. 1-(2,3,4,5.6-PENTACHLOROPHENOXYACELYL)-3,5-DIMETHYL-4-CHLOROPYRAZOLE. 